netxen: protect resource cleanup by rtnl lock

o context resources can be in used, while resource cleanup is in progress,
  during fw recover.
o Null pointer execption can occur in send_cmd_desc, if fw recovery
  module frees tx ring without rtnl lock.
o Same applies to ethtool register dump.

Signed-off-by: Amit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/net/netxen/netxen_nic_main.c b/drivers/net/netxen/netxen_nic_main.c
index 5209095a8739..24279e6e55f5 100644
--- a/drivers/net/netxen/netxen_nic_main.c
+++ b/drivers/net/netxen/netxen_nic_main.c
@@ -2240,7 +2240,9 @@ netxen_detach_work(struct work_struct *work)
 
         netxen_nic_down(adapter, netdev);
 
+        rtnl_lock();
         netxen_nic_detach(adapter);
+        rtnl_unlock();
 
         status = NXRD32(adapter, NETXEN_PEG_HALT_STATUS1);